Impact of climate change on maize production in Ghana. A review

Abstract

Climate change is one of the challenges that human populations and the environment face. In Ghana, agricultural production is expected to be negatively affected because of the projected changes in rainfall regimes and increase in temperatures. Due to the essential role of maize in the food security of the country, numerous studies have been conducted to estimate how its production is being affected now and likely to be affected in future by current and projected changes in climate. In order to assemble the current knowledge of how maize production in Ghana will be affected, a systematic literature review was conducted for published material relating to the topic. From the review, it was apparent that climate change is already happening in Ghana. Available records indicated that temperature has increased by 1oC across the country over the last 30 years. Rainfall has decreased by 20% over the same period. The yields of maize have been affected by these climatic changes. In recent years, there has been a decline in maize yields across the country. Although other contributing factors exist, increasing temperatures and irregularity in rainfall have been cited as the primary causes of the continuous reduction in yields. For future climate projections, the common agreement amongst all the reviewed literature is that maize yields will further decline. The decline varied from 7% in 2020 to 55% by 2050 depending on crop models and emission scenarios used in the study. With a projected increase in population, Ghana is likely to face many challenges in meeting the maize demands by its habitants in the future under the projected climate scenarios. The planting of more heat and drought tolerant maize varieties, adjustments in the planting dates and increasing irrigation facilities in maize production were the commonest adaptation measures identified.